Overlapping Welds for Lethal service in accordance to ASME BPVC Section VIII Div. 1
Overlapping Welds for Lethal service in accordance to ASME BPVC Section VIII Div. 1
(OP)
Hello,
I have a vertical vessel in Lethal Service, construction code ASME VIII Div.1, material SS 316/316L from plate, fully radiographed.
This vessel has many stub-end connections and 3 legs with reinforcement pads as support.
I have to choose where to put the longitudinal weld of the shell.
Only 2 choices (I can't change nozzles' placement):
1) Longitudinal weld which intersects 2 stub-end nozzles, so it will be interrupted, BUT full visible
2) Longitudinal weld which doesn't intersect any nozzles, BUT is covered for a small section by a reinforcement pad of the legs.
Longitudinal weld is fully radiographed, even the section under the pad.
Are both solutions above accepted by ASME? In what article is written?
See also interpretation BPV VIII-1-17-11 and this thread http://www.eng-tips.com/viewthread.cfm?qid=411171
Thank you
I have a vertical vessel in Lethal Service, construction code ASME VIII Div.1, material SS 316/316L from plate, fully radiographed.
This vessel has many stub-end connections and 3 legs with reinforcement pads as support.
I have to choose where to put the longitudinal weld of the shell.
Only 2 choices (I can't change nozzles' placement):
1) Longitudinal weld which intersects 2 stub-end nozzles, so it will be interrupted, BUT full visible
2) Longitudinal weld which doesn't intersect any nozzles, BUT is covered for a small section by a reinforcement pad of the legs.
Longitudinal weld is fully radiographed, even the section under the pad.
Are both solutions above accepted by ASME? In what article is written?
See also interpretation BPV VIII-1-17-11 and this thread http://www.eng-tips.com/viewthread.cfm?qid=411171
Thank you





RE: Overlapping Welds for Lethal service in accordance to ASME BPVC Section VIII Div. 1
Good engineering practice in lethal service: all pressure welds must be pass leak test (Helium…..).
Delete the pad of the legs. Try to use 4 legs instead of 3 to reduce stresses, if necessary.
Regards
r6155
RE: Overlapping Welds for Lethal service in accordance to ASME BPVC Section VIII Div. 1
Not acceptable according to...? ASME? Or only to good engineering practice?
RE: Overlapping Welds for Lethal service in accordance to ASME BPVC Section VIII Div. 1
Please, read more about lethal service.
Regards
r6155
RE: Overlapping Welds for Lethal service in accordance to ASME BPVC Section VIII Div. 1
https://pveng.com/lethal-service-notes/
Maybe you can find what you are looking for.
Regards.
RE: Overlapping Welds for Lethal service in accordance to ASME BPVC Section VIII Div. 1
RE: Overlapping Welds for Lethal service in accordance to ASME BPVC Section VIII Div. 1
I think the only solution could be 1): in this case all the seam will be full visible, although interrupted.
r6155 why 1) is not acceptable?
RE: Overlapping Welds for Lethal service in accordance to ASME BPVC Section VIII Div. 1
Clean design is mandatory for lethal service, like nuclear.
Your design under 1) is wrong for normal service too.
Sorry, you are not in conditions to design for lethal service.
Regards
r6155
RE: Overlapping Welds for Lethal service in accordance to ASME BPVC Section VIII Div. 1